Infectious diseases caused by pathogenic microorganisms, viruses or parasites are a major threat to human health, and lead to 16.2% of the world's annual deaths. Discovery of effective therapeutics is urgently needed to fight these diseases and save lives. Pradimicin A is an antifungal and antiviral natural product from Actinomadura hibisca P157-2. Development of pradimicins into anti-infective drugs has been hampered by their poor water solubility and side effects. To take advantage of the significant biological activities of pradimicin A and find promising anti-infective drug candidates, this Academic Research Enhancement Award (AREA) R15 application is to study the biosynthetic pathway of pradimicin A and generate novel pradimicin analogs using both enzymatic and chemical methods. Three central hypotheses for the proposed research are: 1) The complete pradimicin A biosynthetic pathway can be reconstituted and engineered in a heterologous host;2) Foreign sugar moieties and the corresponding glycosyltransferases can be engineered into the pradimicin biosynthetic pathway;and 3) New pradimicin analogs such as those with different amino sugars have antifungal and antiviral activities. The investigators will test these central hypotheses and accomplish the overall objective of this project by pursuing four specific aims: 1) Investigate the late tailoring steps in the biosynthesis of pradimicin A;2) Engineer the biosynthesis of novel pradimicin analogs;3) Chemically synthesize novel pradimicin glycosides;and 4) Evaluate the synthesized pradimicin analogs for antifungal and antiviral activities. With the combination of biosynthetic engineering and chemical synthesis, a series of "unnatural" pradimicin analogs will be generated, which may provide novel lead compounds for new anti- infective drug discovery. The PI and two Co-investigators are from three different departments including biological engineering, chemistry and biochemistry, and biology, respectively. Two graduate and four undergraduate students will perform the proposed research, with assistance from a technician. This multi-departmental collaborative project will provide outstanding training opportunities for student researchers, in accordance with R15 grant objectives. The students will benefit from this interdisciplinary project by working with scientists from different departments and with various backgrounds. It is expected that this project will promote collaborative efforts in biomedical research at Utah State University and the involved students will gain hands-on experience in anti- infective drug discovery. PUBLIC HEALTH RELEVANCE: This project aims to generate a library of novel pradimicin analogs using a combination of enzymatic and chemical methods, and evaluate the antifungal and antiviral activities of these synthesized compounds. The objectives of this proposal are consistent with the goals of the NIH Academic Research Enhancement Award (AREA) R15 program, and will have a significant impact on public health by providing promising molecules for new anti-infective drug discovery. This multi-departmental project will be conducted by a team of researchers consisting of three faculty members, a technician, two graduate students, and four undergraduate students.